Control structures in javascript tutorialspoint
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JavaScript provides full control to handle loops and switch statements. There may be a situation when you need to come out of a loop without reaching its bottom. There may also be a situation when you want to skip a part of your code block and start the next iteration of the loop. Show To handle all such situations, JavaScript provides break and continue statements. These statements are used to immediately come out of any loop or to start the next iteration of any loop respectively. The break StatementThe break statement, which was briefly introduced with the switch statement, is used to exit a loop early, breaking out of the enclosing curly braces. Flow ChartThe flow chart of a break statement would look as follows −  ExampleThe following example illustrates the use of a break statement with a while loop. Notice how the loop breaks out early once x reaches 5 and reaches to document.write (..) statement just below to the closing curly brace −
OutputEntering the loop 2 3 4 5 Exiting the loop! Set the variable to different value and then try... We already have seen the usage of break statement inside a switch statement. The continue StatementThe continue statement tells the interpreter to immediately start the next iteration of the loop and skip the remaining code block. When a continue statement is encountered, the program flow moves to the loop check expression immediately and if the condition remains true, then it starts the next iteration, otherwise the control comes out of the loop. ExampleThis example illustrates the use of a continue statement with a while loop. Notice how the continue statement is used to skip printing when the index held in variable x reaches 5 −
OutputEntering the loop 2 3 4 6 7 8 9 10 Exiting the loop! Set the variable to different value and then try... Using Labels to Control the FlowStarting from JavaScript 1.2, a label can be used with break and continue to control the flow more precisely. A label is simply an identifier followed by a colon (:) that is applied to a statement or a block of code. We will see two different examples to understand how to use labels with break and continue. Note − Line breaks are not allowed between the ‘continue’ or ‘break’ statement and its label name. Also, there should not be any other statement in between a label name and associated loop. Try the following two examples for a better understanding of Labels. Example 1The following example shows how to implement Label with a break statement.
OutputEntering the loop! Outerloop: 0 Innerloop: 0 Innerloop: 1 Innerloop: 2 Innerloop: 3 Outerloop: 1 Innerloop: 0 Innerloop: 1 Innerloop: 2 Innerloop: 3 Outerloop: 2 Outerloop: 3 Innerloop: 0 Innerloop: 1 Innerloop: 2 Innerloop: 3 Outerloop: 4 Exiting the loop! Example 2
OutputEntering the loop! Outerloop: 0 Innerloop: 0 Innerloop: 1 Innerloop: 2 Outerloop: 1 Innerloop: 0 Innerloop: 1 Innerloop: 2 Outerloop: 2 Innerloop: 0 Innerloop: 1 Innerloop: 2 Exiting the loop! What are control statements in JavaScript?Control statements are designed to allow you to create scripts that can decide which lines of code are evaluated, or how many times to evaluate them. There are two different types of control statements: conditional statements and loop statements.
What are the three possible forms of control expressions in JavaScript?There are three Iterative statements: WHILE, DO-WHILE and FOR. Let's understand each with syntax. one of the control flow statement, which executes a code block when the condition is satisfied. But unlike IF, while keeps repeating itself until the condition is satisfied.
What are control statements with example?The examples in this section show various uses of the Postprocessor. All the examples include the DATE statement to illustrate how the value specified for DATE relates to the value specified for RTOD, ETOD, or STOD to define the reporting period.
What is control statements Tutorialspoint?Control statements are the statements that change the flow of execution of statements. For example, If, If-else, Switch-Case, while-do statements.
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